Hundreds of people turned out for a forum on the proposed extension of the Long Beach (710) Freeway on Sept. 18, 2012, at the Pasadena Convention Center. Panelists said a new tunnel would likely cause air pollution problems.

Hundreds of people turned out for a forum on the proposed extension of the Long Beach (710) Freeway on Sept. 18, 2012, at the Pasadena Convention Center. Panelists said a new tunnel would likely cause air pollution problems.

Cheryl A. Guerrero/Staff Photographer

Hundreds of people turned out for a forum on the proposed extension of the Long Beach (710) Freeway on Sept. 18, 2012, at the Pasadena Convention Center. Panelists said a new tunnel would likely cause air pollution problems.

Hundreds of people turned out for a forum on the proposed extension of the Long Beach (710) Freeway on Sept. 18, 2012, at the Pasadena Convention Center. Panelists said a new tunnel would likely cause air pollution problems. (Cheryl A. Guerrero/Staff Photographer)

Hundreds of people turned out for a forum on the proposed extension of the Long Beach (710) Freeway on Sept. 18, 2012, at the Pasadena Convention Center. Panelists said a new tunnel would likely cause air pollution problems.